1. Field of the Invention
The present invention relates to a display device suitable for use in a photographic camera.
2. Description of the Prior Art
It has heretofore been proposed that a liquid crystal display and LED display may be realized in a single display device, this proposal having been disclosed, for example, in Japanese Utility Model Laid-open No. 181738/1985. The proposed prior art enables a display device in which a single display unit is capable of displaying both a liquid crystal display image and a translucent display image which is obtained by illuminating translucent marks or symbols with light emitted from associated light emitting diodes. More specifically, a mask member is superimposed on a liquid crystal display panel on which the liquid crystal display image is formed. The mask member is provided with a liquid crystal display image area and translucent marks or symbols disposed in the form of translucent display windows for forming the translucent display images, the thus-obtained liquid crystal and translucent display images being arranged in a row. In addition, light emitting means employing LEDs is disposed in the vicinity of the mask member in such a manner that illuminating light is transmitted through the translucent display windows.
One problem raised by such a display device is how the space between the liquid crystal display image and the translucent display image can be made narrow so as to display these two images as closely as possible. For example, if the liquid crystal display panel is provided with a laterally elongated liquid crystal display image area with respect to the elongated shape of the mask member, the translucent display image must be separated from the liquid crystal display image by a distance equivalent to the thickness of the portion of the liquid crystal display panel in which the liquid crystal is enclosed. Otherwise the translucent display image may be illuminated by the light transmitted through the liquid crystal display panel. In order to solve the above-described problems, it is also considered that the liquid crystal display panel and the mask member should be formed so as to have substantially the same lateral length, the translucent display image may be illuminated by the light transmitted through the liquid crystal display panel. This method is effective when the liquid crystal employed is of a positive type (in which light is normally transmitted through all portions other than the segment electrodes), but it is impossible to use this method when the liquid crystal is of a negative type (in which light is normally shielded by all the portions other than the segment electrodes). In recent years, the negative type liquid crystal has increasingly been used for the purpose of displaying a clear liquid crystal display image even when the illuminating light is of a low intensity (for example, a variable digit display using characters of a rectangular 8 shape constituted by segment electrodes). In consequence, demand has arisen for development of an arrangement in which it is possible to narrow the space between the translucent display image and the liquid crystal display image formed by the negative type liquid crystal.